Grommets have a marine/ nautical application. Anytime a sailmaker wants to pass a line through canvas, he will install a sewn grommet. Hervey Garrett Smith The Marlinspike Sailor pp.15-16 shows you how it's done. An equally good book, and more available is Arts of the Sailor, same author. These are both excellent 1950s era books written when pleasure boats were wood, canvas, and hemp and smelled of tar and paint and a skipper was expected to do his own maintenance, written by a man who grew up around boats at the end of the 19th century. The tech is ancient because it worked and changing the way it should be done would get you killed. If you are rigging canvas, and you want to look like you know what you are about, even if it is a lean to, then follow Smith's guide. Your gear will wear and last longer and look timeless.

Hammered in metal grommets? The earliest that I know of is in the 1820's, the reference is on corsets. I did find a that sail eyelet grommets were used later in the 1840's. That's about it. For 18th century youo are going to have to stitch them.

those sail eyelet grommets were likely still the brass thimbles. I can't find documentation of any sort of metal eye that size till about the 1890's.

Small ones on shoes and corsets started about 1880. Even for corsets, I've not found earlier.

The good thing is, seems the stitched grommet (grimble) with the brass thimble hammered into it dates prior to 1600.

Not a burden though. With the stitched ones, you can not only reinforce with more material, but change your stitch pattern for strength in the direction of pull. That is something metal ones donít do and why they end up tearing or popping out in high wind.

The use of metal grommets goes back to the 12th century, They are different than what is commonly used today. Early grommets were metal rings of the appropriate size for the intended use, these were then sewn in place to provide a strong hole to secure rope or cording. Medevil sails used this method to attach ropes, it was used extensivly on clothing especialy in the 1500s and later. If you are building something that needs grommets prior to the mid 1800s then you would want to use this method. It is more time consuming to do than a hammered grommet, but much more original. My wife is a seamstress who specializes in period clothing, and i have made the rings for several peices she has made and hand sewn the rings in place. This method is alot more durable than the hammered in type and less likly to rip out.